diff --git a/main/shortening-layer/src/main/java/org/cryptomator/shortening/ShorteningFileSystem.java b/main/shortening-layer/src/main/java/org/cryptomator/shortening/ShorteningFileSystem.java
index 3923d1837..ce7d7a899 100644
--- a/main/shortening-layer/src/main/java/org/cryptomator/shortening/ShorteningFileSystem.java
+++ b/main/shortening-layer/src/main/java/org/cryptomator/shortening/ShorteningFileSystem.java
@@ -1,21 +1,19 @@
 package org.cryptomator.shortening;
 
-import java.util.Optional;
-
 import org.cryptomator.filesystem.FileSystem;
 import org.cryptomator.filesystem.Folder;
 
+/**
+ * Filesystem implementation, that shortens filenames when they reach a certain threshold (inclusive).
+ * Shortening is done by SHA1-hashing those files, so a threshold below the length of the hashed files makes no sense.
+ * Hashes are then mapped back to the original filenames by storing metadata files inside the given metadataRoot.
+ */
 public class ShorteningFileSystem extends ShorteningFolder implements FileSystem {
 
 	public ShorteningFileSystem(Folder root, Folder metadataRoot, int threshold) {
 		super(null, root, "", metadataRoot, new FilenameShortener(metadataRoot, threshold));
 	}
 
-	@Override
-	public Optional<ShorteningFolder> parent() {
-		return Optional.empty();
-	}
-
 	@Override
 	public boolean exists() {
 		return true;
diff --git a/main/shortening-layer/src/test/java/org/cryptomator/shortening/ShorteningFileSystemTest.java b/main/shortening-layer/src/test/java/org/cryptomator/shortening/ShorteningFileSystemTest.java
index 0917fb2d6..0cf131fc3 100644
--- a/main/shortening-layer/src/test/java/org/cryptomator/shortening/ShorteningFileSystemTest.java
+++ b/main/shortening-layer/src/test/java/org/cryptomator/shortening/ShorteningFileSystemTest.java
@@ -2,6 +2,7 @@ package org.cryptomator.shortening;
 
 import java.io.UncheckedIOException;
 import java.nio.ByteBuffer;
+import java.time.Instant;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
 
@@ -47,6 +48,41 @@ public class ShorteningFileSystemTest {
 		Assert.assertTrue(correspondingMetadataFile.exists());
 	}
 
+	@Test
+	public void testMoveLongFolders() {
+		final FileSystem underlyingFs = new InMemoryFileSystem();
+		final Folder metadataRoot = underlyingFs.folder("m");
+		final FileSystem fs = new ShorteningFileSystem(underlyingFs, metadataRoot, 10);
+
+		final Folder shortNamedFolder = fs.folder("test");
+		shortNamedFolder.create(FolderCreateMode.FAIL_IF_PARENT_IS_MISSING);
+		Assert.assertFalse(metadataRoot.children().findAny().isPresent());
+
+		final Folder longNamedFolder = fs.folder("morethantenchars");
+		shortNamedFolder.moveTo(longNamedFolder);
+		Assert.assertTrue(metadataRoot.children().findAny().isPresent());
+	}
+
+	@Test
+	public void testMoveLongFiles() throws UncheckedIOException, TimeoutException {
+		final FileSystem underlyingFs = new InMemoryFileSystem();
+		final Folder metadataRoot = underlyingFs.folder("m");
+		final FileSystem fs = new ShorteningFileSystem(underlyingFs, metadataRoot, 10);
+
+		final File shortNamedFolder = fs.file("test");
+		try (WritableFile file = shortNamedFolder.openWritable(1, TimeUnit.MILLISECONDS)) {
+			file.write(ByteBuffer.wrap("hello world".getBytes()));
+		}
+		Assert.assertFalse(metadataRoot.children().findAny().isPresent());
+
+		final File longNamedFolder = fs.file("morethantenchars");
+		try (WritableFile src = shortNamedFolder.openWritable(1, TimeUnit.MILLISECONDS); //
+				WritableFile dst = longNamedFolder.openWritable(1, TimeUnit.MILLISECONDS)) {
+			src.moveTo(dst);
+		}
+		Assert.assertTrue(metadataRoot.children().findAny().isPresent());
+	}
+
 	@Test
 	public void testDeflateAndInflateFolder() {
 		final FileSystem underlyingFs = new InMemoryFileSystem();
@@ -82,11 +118,15 @@ public class ShorteningFileSystemTest {
 	}
 
 	@Test
-	public void testPassthroughShortNamedFiles() throws UncheckedIOException, TimeoutException {
+	public void testPassthroughShortNamedFiles() throws UncheckedIOException, TimeoutException, InterruptedException {
 		final FileSystem underlyingFs = new InMemoryFileSystem();
 		final Folder metadataRoot = underlyingFs.folder("m");
 		final FileSystem fs = new ShorteningFileSystem(underlyingFs, metadataRoot, 10);
 
+		final Instant testStart = Instant.now();
+
+		Thread.sleep(1);
+
 		// of folders:
 		underlyingFs.folder("foo").folder("bar").create(FolderCreateMode.INCLUDING_PARENTS);
 		Assert.assertTrue(fs.folder("foo").folder("bar").exists());
@@ -100,6 +140,7 @@ public class ShorteningFileSystemTest {
 			file.read(buf);
 			Assert.assertEquals("hello world", new String(buf.array()));
 		}
+		Assert.assertTrue(fs.folder("foo").file("test1.txt").lastModified().isAfter(testStart));
 
 		// to underlying:
 		try (WritableFile file = fs.folder("foo").file("test2.txt").openWritable(1, TimeUnit.MILLISECONDS)) {
@@ -110,6 +151,7 @@ public class ShorteningFileSystemTest {
 			file.read(buf);
 			Assert.assertEquals("hello world", new String(buf.array()));
 		}
+		Assert.assertTrue(fs.folder("foo").file("test2.txt").lastModified().isAfter(testStart));
 	}
 
 }